1. The name of certain substances which are mixtures of silex and alumin, sometimes with lime, magnesia, alkali and metallic oxyds. A species of earths which are firmly coherent, weighty, compact, and hard when dry, but stiff, viscid and ductile when moist, and smooth to the touch; not readily diffusible in water, and when mixed, not readily subsiding in it. They contract by heat. Clays absorb water greedily, and become soft, but are so tenacious as to be molded into any shape, and hence they are the materials of bricks and various vessels, domestic and chimical.
2. In poetry and in scripture, earth in general.
3. In scripture, clay is used to express frailty, liableness to decay and destruction.
They that dwell in houses of clay Job 4:19.
CLAY, verb transitive
1. To cover or manure with clay
2. To purify and whiten with clay as sugar.